The present invention pertains to a fluid coupling and system for use thereof and more particularly to a quick-connect and -disconnect fluid coupling having coupling members that are quickly connectable and disconnectable and to a system which incorporates in the coupling different matching key-coded elements that ensure not only quick connection but connection of only those coupling members that match.
In various industries, it is necessary to use many chemicals in the manufacturing process. For example, in the semiconductor industry, some fifteen to twenty liquid chemicals are typically stored in adjacent fifty-gallon drums from which they are dispensed during the manufacture of the semiconductors. In the usual installation, sets of umbilical delivery lines for various chemicals are suspended above the drums with a particular set dedicated to a particular chemical. Each set of delivery lines is connected to its associated drum by a coupling which has one coupling member on the delivery lines and a second coupling on the drum.
As each drum is emptied during the manufacturing process, a full drum is brought in to replace the empty one. Accordingly, the coupling members must be repeatedly connected and disconnected. Because of the incompatibility of the chemicals, it is critical that each set of delivery lines be connected only to its intended drum to avoid unsafe mixing and undesired contamination. Moreover, to maintain productivity, such connections and disconnections must be made quickly and routinely by production personnel.
To insure correct connection of delivery lines to their intended drums, the known chemical extraction apparatus uses fluid couplings that incorporate matching coding elements on the coupling members. Examples of such fluid couplings and their coding devices are shown and described in the U.S. Pat. No. 4,699,298 to Grant et al. and U.S. Pat. No. 5,108,015 Rauworth et al. A significant disadvantage of these known couplings, however, is that they cannot be as quickly connected and disconnected as is desired. Although referred to as quick-connect couplings, they use threads to establish the connection. Repeated threading and unthreading of couplings over a production run consumes a significant amount of valuable time and also can produce additional delays if the threads become fouled and otherwise fail to mesh properly. Moreover, the coding devices of these known couplings require relative rotation of the coded parts to test for a match and then to make the match or to realize that the coupling members are mismatched.
Fluid couplings that can be connected and disconnected without threading are of course available and are truly quick-connect and -disconnect couplings. Examples of known quick-connect couplings are disclosed in U.S. Pat. No. 4,436,125 to Blenkush and U.S. Pat. No. 5,052,725 to Meyer et al. Such known couplings of this type, however, are not suitable for the chemical extraction industry or other industries where matched connections are mandatory since they make no provision for coding. Moreover, the latching mechanisms used in such known quick-connect couplings do not lend themselves to balanced and dependable two-handed operation by personnel in production processes such as described above.
A quick-connect coupling is provided for enabling interconnection of only matching coupling members while preventing the inadvertent interconnection of mismatched coupling members notwithstanding the presence of a plurality of coupling members some of which are matched and some of which are mismatched. The coupling includes first and second coupling members that are releasably slidably, axially interfitted with their passageways in fluid communication. Key coding elements on the coupling members are movable into matched interengagement when the coupling members are matched but are precluded from moving into matched interengagement when they are mismatched. If a match exists, the coding elements interfit without relative rotation of the coupling members and irrespective of the relative rotational positions of the coupling members prior to such interengagement. Latches in the coupling are allowed by the key coding to move into latching positions when the key coding elements match but are precluded by the key coding from moving into latching positions when there is a mismatch. The subject key coding system is especially advantageous in providing a user with immediate visual indications of whether particular coupling members are matched or mismatched. The coupling members are coupled by simply axially thrusting the members together whereupon the latches move out to allow interfitting and then return to latching positions. The coupling members are uncoupled by simultaneously pressing inwardly on the latches on the outside of the coupling and pulling the coupling members apart.
An object of this invention is to provide an improved quick-connect coupling.
Another object is to provide a quick-connect and disconnect coupling for use in a chemical extraction system involving drums of chemicals and delivery lines suspended above the drums.
A further object is to improve the productivity and safety of dispensing a plurality of incompatible chemicals through different delivery lines from different drums in a manufacturing process.
A still further object is to provide an improved coding system for enabling desired interconnection of only matched coupling members of a fluid coupling.
Yet another object is to incorporate a coding system for a quick-connect coupling that prevents coupling of mismatched coupling members while still allowing quick connection and disconnection of the coupling.
An additional object is to code fluid coupling members so that, apart from a visual inspection, testing for a match and establishing a coupling is accomplished without relative rotation and solely by axial movement of the coupling members and without regard to the relative rotational positions of the coupling members prior to or during interfitting thereof.
A still further object is to provide a key-coded, quick-connect coupling that does not require swiveling of its coupling members for connection but permits the parts being coupled to swivel without affecting the rapidity of interconnecting matched coupling members and without affecting operation of coupling.
A further object is to minimize the time required dependably to connect matched coupling members of a coded coupling or to determine that the coupling members are mismatched and will not couple.
Another object is to provide a coded quick-connect coupling composed of parts that are molded or machined of plastic materials and that has molded-in identification of the codes.
An additional object is to provide a key coding system for a coupling that enables many different combinations of matches and mismatches.
Yet another object is to provide a molded one-piece latch for a fluid coupling.
A further object is to provide a dual latch assembly including pair of duplicate molded latches for a coupling that can be made using the same mold.
Another object is to provide a symmetrical latching mechanism for a quick-connect coupling.
An additional object is to provide a quick-connect coupling which has dual latching members on one of the coupling members that engage latching elements on both sides of the other coupling member in the coupled or latched condition.
A still further object is to provide a latching mechanism for a quick-connect coupling in which the external appearance of the latches indicates the coupled or uncoupled status of the coupling.
Still another object is to provide integral molded latches for a fluid coupling in which resiliently flexible biasing arms for the latches are not exposed externally of the coupling.
Another object is to isolate the latches of a quick-connect coupling from the fluids carried by the coupling.
A further object is provide a quick-connect fluid coupling in which latches are captured in the coupling by the assembly thereof.
Yet an additional object is to provide a quick-connect coupling which automatically snaps into coupled position upon axially thrusting the coupling members together but which requires simultaneous, two-handed pressure on opposite sides of the coupling to release the coupling members.
A further object is to provide a coded, quick-connect coupling with improved sealing capabilities.
Yet another object is to provide an interactive key coding system and latching mechanism in a quick-connect coup ling wherein the coupling members cannot be coupled unless they match.
Still further, an object is to minimize the twisting and tangling of the umbilical lines that hang above a plurality of drums of chemicals used in a chemical manufacturing process and that are connected and disconnected to and from selected drums.
A further object is to minimize the manufacturing costs of a quick-connect coupling.
Another object is to provide a fluid coupling where in first and second coupling members respectively connected to a source of fluid and to delivery lines are repeatedly uncoupled and recoupled and wherein fluid is allowed to drain back into the source and out of the coupling during such uncoupling and recoupling.
Still another object is to provide a fluid coupling for use on a typical fifty-five gallon drum containing liquid for the chemical processing industry which has an extractor drum insert and bung that are compatible with the bung hole, rim, and other characteristics of such a drum, and which can withstand the drop tests required of such drums and their standard bungs.
A further object is to facilitate the assembly of the parts of one of the coupling members that is incorporated in the extractor head of a chemical extraction coupling.
These and other objects, features and advantages of the present invention will become apparent upon reference to the following description, accompanying drawings, and appended claims.